Will someone please provide a link to the proper adapter to hardware my Max Transit Duo to a dedicated 20amp circuit in my RV? The specs to find an adapter are good, but a link to an actual adapter that I can buy is better. Thank you.
As in from a breaker or fuse board right? Guess it all depends on your fit / finish distance from the supply.
Personally I would use 14AWG cable throughout. And - ignorant of your installation capabilities as I am, suggest this to go from 20amp source to provide an inline fuse and an industry standard SAE connector:
Then this to go from the SAE connector to the Tranist:
But all you really need is a good quality cable between the power source and the green terminal block on the transit with an inline fuse @ 5A to be safe.
Thank you Martin.
To give you some more perspective, I have been using a WifiRanger GoAC router in my RV for about a year. I had a 20amp circuit run from the fuse panel to the equipment closet just for this router - it is currently hardwired to the circuit with their hardwire adapter.
I’m going to continue using this hardwired power input for my WifiRanger EliteAC antenna that will be a WAN input to the Peplink MTD (since the POE injector adapter they provide uses the same barrel plug).
I want to tie into the same circuit with the Peplink with a similar transform/adapter and am looking for this. I also have USB outlets to use for the USB-C 2amp inputs to the Peplink BUT I want this to be a backup, using the hardwired solution to the Peplink terminal block.
I hope this makes it more clear - I should have explained more in the first place.
This is what I have now. It will power the Elite AC antenna.
Understood, but just to be sure is the 20AMP circuit AC mains voltage or 12/24V DC voltage?
Looking at the image above it looks like a Mean Well RSD-30 30W Isolated DC-DC Converter. Which is a chassis mount unit and supports 9 → 36 V DC in, and provides 24V DC out and is often used for railway applications.
You could just buy another one of those. They are About 29USD and it would power the transit fine.
Yes Martin. It is DC.
I’ve converted nearly everything in my RV to 12v.
This, like I mentioned, currently powers my WifiRanger router.
Thanks for the info about the converter.
Do you think I could power both the Peplink and the WifiRanger antenna (via a POE) injector with only one of these. Peplink MTD is 18W, WifiRanger is 11W, totalling 29W. The output capacity for this converter is 30W.
Could I double up the output terminals? I’m lame when it comes to power options.
Or a barrel plug splitter - 1 in, 2 out?
Yes I do. Buy a heavy duty 2.1mm DC extension cable, chop the female end off and attached the wires to the terminals where the current 2.1mm DC plug is connected.
But check polarity with a multi-meter, make sure the pin is positive and the barrel negative - then you’ll be fine.
I’ll give it a try.
I may just plug a 2.1mm pigtail into the existing barrel attached (I know the polarity is currently correct since I use this for the GoAC router). I have a multi-meter if I go to the splicing suggestion.
You were right. The single converter powered both my Max and the Mikrotik Metal with a 1 to 2 barrel adapter.
I have a new problem now. I’ve added a Netgear 8-Port Gigabit Smart Managed Plus Switch that has a 48v input requirement. I’ll use this to power the Mikrotik on one of its POE ports. I found that the current converter with 1 to 2 barrel adapter won’t power the switch.
Do you think that your other recommendation for the Aweking Waterproof DC/DC 12V Step Up to 48V will work with my new configuration? Should I get the 3 or 6 amp version of this? I’m thinking 6 amp for future-proofing. I also have a 12v TV and 12v BluRay on the same 12gauge 12v circuit.
I’m am totally lame when it comes to power stuff. All I know is that the new Netgear switch won’t integrate without changing something in the power management.
Any good quality step up DC/DC convertor should work. What current rating is the OEM DC PSU for the netgear? That would act as a guide for whether to go for the 3A (144W)or 6A (288W) DC/DC convertor.
- NG switch - 48V @ 1.25 amps (powers 4 POE+ ports at 15.4w/each)
- Max Transit - 12 - 48v @ 2 amps
- TV - 12v @ 1.2 amps
- a couple of marine-grade cig lighter receptacles
Do I just add the amp requirements of the devices to be powered?
If so, 6 amp version of the converter? Is the Aweking that you mention good or should I look for something with better quality?
You add the power requirements yes. So the netgear switch is firstname.lastname@example.orgA for a total of 60W The transit is 18W max according to the datasheet (so <0.4A @ 48V). You could get away with the 48V 3A DC/DC for these no problem - although I always double up for future proofing and so things don’t run hot so buy a 5-6A rated 48V booster convertor.
Obviously these 12V applications should not be fed from the 48V side of the convertor…
Its not a recommendation - I’ve never used that brand, just a suggestion.
Because I use to many of these things I get my own manufactured to order now. The good news is that the components in general are typically reliable and with the cast aluminium heatsink on an overrated unit (the 6A instead of the 3A in your case) its very unlikely to go wrong.
Must have shipped 300-400 voltage regulators in enclosures now and only ever had one fail in the field and that was I suspect due to the customer plugging in some nasty high voltage power source (over voltage, short circuit and over temp are all in built safety features).
I’ll have to take a close look at the rat’s nest of wires that the installer left. I’m not sure if the TV, BluRay, cig lighter adapters are on the same converter (Mean Well 12/24) or not. If I’m replacing the Mean Well with the 48v, this would be a problem for the lesser demanding devices.
I’m tempted to just NOT have a switch since everything works fine at this point. Or, I can just plug the switch into 110 when I need it. I would hate to have to replace the Mean Well, AND separate out a 12v branch on the single circuit that’s been installed. I’m just not that good with power stuff.
Hello Martin. I ran a new 12v circuit (20 amp fuse) from my fuse box to the equipment closet. I did this so-as to put the 12 > 48v step-up converter for the new switch. Now, I have another device that requires 19v @ 2.1a. I don’t really want to run another circuit from the fuse box. Can I attach TWO step-up converters (one 12>48 and one 12>19) to the same circuit? The current from the fuse box is adequate to power both the 48v and 19v loads. I just don’t know if two step-ups on a single wire is OK. I’m not talking about wiring the step-ups in parallel or series, just two isolated step-ups on the same wire. I have Googled until blue in the face and can’t find a direct answer to this. Thank you, as always!
Yes - that’s fine. The inputs for the two voltage regulators / convertors can be powered from the same 12V circuit.
If you wanted to be extra safe you could put inline fuses on the individual 12V regulators but the whole point of those buck boost devices (over and above voltage level change) is the added protection against over current / over voltage so you don’t technically need to.
Thanks Martin. The main 12v circuit is fused (choice of 10, 15, 20 amp fuse). The two devices are the 48v/1.15a switch and a 19v/2.1a Nvidia Shield streamer. Each will have the appropriate step-up converter. What additional fuses would you recommend, and where in the line? Should I have additional fuses somewhere in the converter wiring after I splice it into the 12v main circuit (what fuse amperage?), or on the 12v feed line (already a fuse at the fuse box). Since I’m only drawing a total of under 4 amps from the two loads, should I just use a 10 amp fuse at the fuse box?
Here’s what I’ll use to splice the two step-up converters into the 12v circuit, then shrink insulate them.
I am learning A LOT from you my friend.
I use step up in the marine environment. Always go bigger than you need in terms of amps/watts, it will mean the step up device lasts longer and doesnt get as hot. Make sure everything is properly fused or alternatively use circuit breakers instead of fuses.
I’m using this between the 48v step-up and the 48v switch, but with a 5amp fuse. I’ll snip the ring connectors off and connect the leads directly to the step-up converter.
Then I have an SAE connector wired to the terminal block on the switch. This allows easy connect when I move it from RV to house.
I’ll check polarity all the way down the circuit. SAE connectors can be tricky with their wiring colors.
I’m assuming that it’s OK to use this on a 48v circuit since it’s 14AWG and just wires. SAE connectors are rated for higher voltage and about 15 amps. The load will pull max 1.2 amps at 48v and 4.1 amps at 12v. I think I’m OK with this setup since the amps are low.
Yup. You certainly are!
Here’s my circuit work that I’ll be doing on Friday. If you see anything amiss, please let me know. I don’t have a problem building the circuit, soldering and so forth. But, I am not an electrician and everything you see is based on research, not experience. SAE is tricky since the way the connectors connect don’t show the red wire continuity correctly. I’ll wire the SAE plug with fuse accordingly so that the wires that I see do correspond red = plus and black = minus. That’s why I have the polarity check reminder at the bottom (my reminder).
Also, all wire UP TO the step-up converters (including the switch wiring) is 10AWG (10 feet from fuse box to switch). All wires from step-up to loads (all 1 - 2 foot lengths) are 14AWG except the wires attached to the step-up converters themselves - I believe that they are 16AWG.
The most important thing to know, although I’ve researched pretty well, is if I have adequate fusing in the circuit - the fuse amperage choice was based on the load devices amperage specification at 12v (making it higher) even though the loads are beyond the 48v step-up converters. At 48v, the amperage is very low, so I’m wondering if the fuses will be effective. The fuses are at least 1.5 times the expected max draw (amps based on 12v) by the router and Shield device.